All posts by jb38
Below are all of jb38's postings, with the most recent are at the bottom of the page.
brian: It depends on what's meant by "then they go again", because once a TV or box has been tuned it should never require retuning again unless a notice to this effect has been seen, as any time that selecting a channel results in a blank screen its usually always due the signal received being on the weak side to the extent that its hovering near to the receivers signal level cut off threshold and is jumping in and out of same, and NOT because of the channel having been lost from the tuners memory.
That said, in some older equipment (and not that much so) if more channels are picked up during multiple rescans than the tuners memory capacity can hold then they just drop out again as soon as the TV or box is switched off, this being why that its always advisable to carry out a complete factory reset (default setting or first time installation) before carrying out an auto-tune, this in your particular TV being called "reinstall all services".
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martin brown: Thanks for the update, although I did say - on each these of these five "muxes" - shortly after having mentioned the plus points of using a Humax box for tests, the programmes in brackets at the side of the mux channels simply given to represent an EPG programme number used by each of the individual mux, and which would have saved you using the manual tune test if you had selected the programme then checked the levels (called "condition" on most Humax's) although obviously this short cut would not be applicable unless all muxes had previously been stored.
However levels measured only using the 9300 is perfectly suffice for accuracy, as indeed are levels measured on any Humax by them being more in line with the reality of the situation compared to indications taken from most other devices, and even although the 9300 cannot indicate HD quality levels (albeit that it does strength) this is neither here nor there.
As far as your signal readings are concerned, these are roughly in line with what was expected when taking the problem you referred to into account, and as you will most probably have gathered the problem encountered unfortunately being of a nature where about the only action that could be taken at the receiving end in an attempt to improve reception being to carry out some experiments with an alternative aerial position, such moving the aerial slightly to the left or right, higher or lower, or a combination of both, because other than trying that I don't see any chances of the signal improving except by that caused by seasonal changes.
The reason for saying this being, I suspect that the problem is mainly being caused by the propagational differences of the new frequency, this always occurring to a certain degree but with it always having a greater effect on reception for viewers who might reside in an area where the signal path from the transmitter is being partially obstructed at some point along the way, which indeed I noticed applies with a number of people who made complaints, knowledge of their post code allowing the terrain indicator to be accessed, the possibility of this being applicable in your case being unknown.
That said though, there is also the possibility that the problem is being partially caused by a very slight phase matching deficiency between the radiating panels used on the mast that sweeps across your area and which is now being revealed by the frequency change, and if anything like that did apply a transmitter engineer would be totally unaware of this as the loading indications on the TX would appear as being within limits.
By the way, the panels referred to are arranged in a circular fashion to cover all points of the compass.
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martin brown: A slight alteration to that said as on checking back I see that you initially did indicate your location, which on checking the signal path to same indicates it being obstructed at approximately 1.5 miles away from you.
The other aspect of the indicator being that it only indicates natural ground obstructions and not anything other than that, such as trees or man made obstacles and which might also be playing a role.
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martin brown: Just noticed that you had already posted a reply about ten minutes or so prior to my addition, it unfortunately being hidden in the masking at the top of my screen, however the change you referred to coincided with channel number changes to the BBC and ArqA mux transmitters and which would obviously involved retuning procedures having been carried out on the transmitters involved as well as an element of aerial matching having taken place to compensate for the change of frequency, and that's what I was referring to.
But though it would be worth trying to make some checks with neighbours for purposes of verifying if they are also experiencing the same problems that you are, because should they be then its extremely doubtful if any experiments carried out on your aerial would have any chance of success, because in cases where moving an aerial in the aforementioned way is successful its usually in systems where differences in levels can be observed with movements from as little as 12" or so , or say maybe from one side of an average loft to the other, or sometimes from a fixed position roof fixing to a suitably positioned gutter mount, aerial type allowing.
But the main reason for suggesting that you first of all make an enquiry with a neighbour is really because that if you go ahead and consult an aerial installer without having made any enquiries then it could well become costly, as the very nature of the procedure I mentioned automatically means that it can be very time consuming by not being an exact science, the whole exercise being basically one of trial and error but which on occasions (and not always) can be highly successful dependant on the situation involved.
Situations where a signal level is high but accompanied by highly erratic quality is one of the most difficult things to deal with "if" the problem is not caused by an intermittent defect on the aerial system, such for example as a bad joint where the coax joins the aerial or indeed a bad joint anywhere in the aerial system, although the time factor of your problem suggests that these latter types of fault conditions mentioned are not likely to apply, unless that is by some unfortunate coincidence!!
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martin brown: Just as a footnote, it should also be kept in mind that engineering notices had been posted to the effect that the service from Winter Hill is liable to interruption from the 8th although no specific dates were mentioned, this being why I would not make any decisions on the policy to adopt just yet but wait an see what happens.
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Keith Evans: The factor you have to remember is that during the period that you have mentioned the transmitters were operating on very low power of approximately 20Kw for the BBC / ITV channels but only half of that on the commercial channels such as the ones you are seeking, and if you were residing in the same locality as you presently are then I am not surprised that you did not receive anything, whereas now the station is operating on full power with the PSB's being on 180Kw and the commercials on 170Kw, a massive difference!
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Keith Evans: By the way the power levels mentioned was with reference to the Sandy transmitters which are located at 30 miles away / 36 degrees and is the only station indicated as providing a reasonable level of reception, whereas Oxford although being nearly 10 miles closer @ 21 miles / 268 degrees is not indicated as being able to give a satisfactory level reception, at least in theory anyway as nothing is exact when dealing with RF signals.
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Steve P: Well I have to admit that I hadn't actually carried out a Google earth check as I was more concerned with finding out what station Linda was picking up that resulted on her having BBC Wales, although I do have distant knowledge of Lytham St Annes by having spent a few holiday breaks in the Fleetwood area and having toured the coastline down to Southport from there.
But though considering what you mentioned about the Moel Y Parc transmitter being virtually line of sight with Lytham its rather odd why DUK's trade view reception predictor gives such poor indications for its reception at Lytham, an indication which is obviously incorrect (and indeed as many are) otherwise Linda's TV / box would not have been picking it up in preference to Winter Hill even although its on a lower mux channel, as going by what's seen indicated for Moel Y Parc suggests that the level received would have been under the threshold level for reception in the Lytham area, albeit obviously not!
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D Matthews: You possibly reside in an area where Freesat might have provided the perfect solution to the problem, that is providing you are not facing into a tree in a S/S Easterly direction and you can accommodate a satellite dish, as satellite reception is for 99.9% of the time totally reliable.
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Saturday 13 April 2013 8:21AM
Michael Campbell: Winter Hill's PSB2 mux channel for ITV1/Ch4/Ch5 etc is Ch59 (778.0Mhz)